Can somebody please help me with this please and thank you.

At 20∘c, the hole in an aluminum ring is 2.800 cm in diameter. you need to slip this ring over a steel shaft that has a room-temperature diameter of 2.804 cm . 1. to what common temperature should the ring and the shaft be heated so that the ring will just fit onto the shaft? coefficients of linear thermal expansion of steel and aluminum are 12×10−6 k−1 and23×10−6 k−1 respectively.

Are formed where bumps from two surfaces come into contact ?

Use the ratio form of kepler’s third law, = , and the data provided to determine the time it takes mars to orbit the sun. round your answer to the nearest tenth. earth’s orbital period = 1.0 earth year earth’s distance from the sun = 1.0 au mars’s distance from the sun = 1.5 au it takes mars about ⇒ 1.8 earth years to orbit the sun.